1. Field of the Invention
The present invention relates to a string-guiding structure for a curtain-reeling device that stabilizes the movement of the string after the string goes through a string-guiding frame and winds on a string-guiding wheel assembly during operation.
2. Description of Related Art
The curtain or blade of a window shade is driven by strings of a curtain-reeling device. Because the curtain-reeling device is attached to an upper rail and the blade is suspended below the upper rail by the strings, two string-guiding wheel assemblies are mounted on two ends of the upper rail and have the strings wound thereon to keep the strings in good stability and proper tension during operation.
However, the speed of the curtain-reeling device to release or collect the strings is fast (no matter whether the curtain-reeling device is a manual or an automatic one), and the strings wound on the string-guiding wheel assemblies easily oscillate or swing to jam themselves to the string-guiding wheel assemblies. Especially one of the conventional string-guiding wheel assembly 1 is composed of multiple rollers 11 pivotally attached inside a frame 12 (as shown in FIGS. 1 and 2), and gaps exist between each of two ends of the rollers 11 and the frame 12 (to reduce the friction force between the rollers 11 and the frame 12 and to make the rollers 11 rotate freely) so that a string 13 might fall into the gaps and influence the smooth operation and tension when the string 13 moves rapidly and reciprocally on the corresponding roller 11 when the string 13 violently and transversally swings and vertically rebounds. Therefore, the conventional curtain-reeling device often malfunctions because of the operational problem that the string 13 gets stuck in the gaps between the rollers 11 and the frame 12 and then jams the curtain-reeling device having no design to limit the oscillation and swing of the string 13.